Midrash for Chullin 278:56
מילין מילין ס"ד
Come and hear: It is written: The likeness of any winged zippor.<span class="x" onmousemove="('comment',' Ibid. IV, 17; with reference to the prohibition of idolatry.');"><sup>31</sup></span>
Sifrei Devarim
(Devarim 22:6) "If there chance before you a bird's nest": to exclude what is normally found there.
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